[PATCH 05/36] autonuma: teach gup_fast about pmd_numa

In the special "pmd" mode of knuma_scand (/sys/kernel/mm/autonuma/knuma_scand/pmd == 1), the pmd may be of numa type (_PAGE_PRESENT not set), however the pte might be present. Therefore, gup_pmd_range() must return 0 in this case to avoid losing a NUMA hinting page fault during gup_fast. Note:

[PATCH 05/36] autonuma: teach gup_fast about pmd_numa

In the special pmd mode of knuma_scand (/sys/kernel/mm/autonuma/knuma_scand/pmd == 1), the pmd may be of numa type (_PAGE_PRESENT not set), however the pte might be present. Therefore, gup_pmd_range() must return 0 in this case to avoid losing a NUMA hinting page fault during gup_fast. Note: